Ground source pumps a ‘sleeping giant’

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This article was published 21/05/2006 (7160 days ago), so information in it may no longer be current.

OTTAWA — Energy-wise, money saving ground source heat pumps are only for large country properties, right?

Wrong.

While that used to be true, the newer versions can be installed on small city lots — either brand new or in some older houses — to reduce heating and cooling costs for homeowners by half to two-thirds. Forget oil, propane or natural gas — get your heat from the earth instead.

“There’s still this perception that you have to be in the country for geothermal,” says John Lobb, marketing director for Earth Energy Solutions, a company that sells what is called a direct exchange (DX) geothermal heat pump that’s built in New Brunswick by Maritime Geothermal. “We can put them on tiny lots,” he says. “That is what makes this different. We look at this as the sleeping giant of the HVAC (heat, ventilation, air conditioning) industry.”

Metric Homes and Cardel Homes of Ottawa offer the DX system as an upgrade. Michel Charlebois, president of Metric Homes, said his company is just about to install the first DX geothermal heat pump into a client’s new home, helping it to easily meet the government’s new Energy Star energy savings qualifications.

While the DX technology has been around since the early 1990s in Eastern Canada, it’s relatively new in Ontario.

Many people here are more familiar with conventional geothermal units that pump water into and out of the ground or use available ground water to pick up heat. They require either lots of space or lots of clean water and a place to dispose of it.

However, the DX system, sometimes known as “urban geothermal,” requires less space and copper pipes instead of plastic to improve the energy transfer.

Here’s how it works: A big drilling machine drills three to five holes (depending on the size of the house) 100 feet deep near or even under the house (if it’s a new construction), plus a two-foot-deep trench from the holes to the house. Everything is covered when they’re done — no pipe caps or boxes on your lawn. A unit the size of a small furnace will sit in your mechanical room.

Two copper pipes — one larger than the other and joined at the bottom — are fed down each hole. An environmentally friendly refrigerant is pumped as a liquid down the smaller copper pipe. When it starts to come back up the larger pipe it changes to a gas, gets colder, and then picks up heat from the surrounding ground in a 20-foot radius. Back at the surface, the gas gets recompressed and it gives off the heat it collected, which warms the air that’s pumped through your house’s air ducts. Electricity runs the equipment.

Wayne Donovan, a retired public servant on a fixed income, has had a DX system for 16 months and has kept close track of the bills, finding it’s saving him even more than he had expected. His 1,850-square-foot bungalow with walkout basement lined with windows has cost him an average of $106 per month in electricity just for heating and air conditioning.

“I’m well ahead of where I thought I’d be,” he says. “I’m saving almost $3,000 a year. That’s money in my pocket.”

Mike Cleland, who runs his own engineering consultation firm, examined all the options and liked the DX for his new home, now under construction, although he found the installation price steep.

While the DX system will cut your energy bills in half, the installation is two to three times the cost of a high-efficiency furnace and air conditioner, ranging from $17,000 to $32,000 depending on the size of house.

However, it will pay itself back in four to six years, and then keep on putting savings in your pocket throughout its lifespan of 20 to 25 years. Today’s furnaces are built to last only about 12 to 15 years.

Lobb flipped to a chart that compares the operating costs of a DX system versus a high-efficiency natural gas furnace: after 20 years and assuming a 15-per-cent annual increase in electricity and natural gas, the DX will save you $139,849 in operating costs, not including the cost of replacing the gas furnace in that time period.

The main force driving sales is people who don’t want to be tied to world oil prices.

“People buy this because they see it’s going to pay them back in the end,” Lobb said. “There are very few really green people.”

That’s where Donovan stands. “The fact it was ecologically the thing to do was a factor, but not the major one,” he said. “The bottom line is, I’m a happy camper. It works.”

For information, check out www.EarthEnergySolutions.ca.

— CanWest News Service